The insulation materials from renewable raw materials have a great potential to decrease the environmental impacts of construction ventures. Here you can see a comparison of the impacts from four different bio-based insulation materials and the nonrenewable alternatives EPS and stone wool per declared unit.
Fiberglass and spray polyurethane foam are derived from by-products of the petrochemical industry and have a high GWP due to their blowing agents. Cotton batts aren’t environmentally friendly either as they require a lot of water and pesticides.
Fossil Fuels
Fossil fuels-coal, oil, and natural gas-have made modern life possible, but they also damage the environment and climate. They form over millions of years from the burial of photosynthetic organisms, including plants on land (that primarily form coal) and plankton in the oceans (that primarily form oil and natural gas). This burial inhibits the movement of carbon through the natural carbon cycle. Burning fossil fuels releases that carbon back into the atmosphere, accelerating climate change and making it harder to recover from natural disasters.
Despite their abundance, fossil fuels are finite resources that will eventually be depleted. When burned, they release large amounts of carbon dioxide into the air, a greenhouse gas that traps heat from sunlight and causes global warming.
The burning of fossil fuels also produces other harmful pollutants. Coal-fired power plants alone produce 35 percent of dangerous mercury emissions in the United States, and they are the leading source of sulfur dioxide, which contributes to acid rain. Air pollution from gasoline-powered cars, trucks, and boats generates toxic toxins like carbon monoxide, nitrous oxide, and soot. These substances have been linked to respiratory and heart problems, and they are responsible for more than 1 in 5 deaths worldwide.
Other by-products of the fossil fuel production process include petrochemicals, used to make everything from plastics to medicines. To make petrochemicals, fossil fuels must be mined from the ground, drilled out of wells, and then refined through complicated chemical processes. The transportation of raw and refined fossil fuels takes many forms, from large tanker ships to trains to trucks.
Chemicals
A major part of the environmental impact of insulation materials is the chemicals used to produce them. Some of these chemicals, such as Styrofoam, contain petroleum byproducts that have a negative impact on the environment. Using insulation that is made from recycled materials can help reduce the need for these products. This also helps to reduce the demand on natural resources and the amount of waste that is produced.
Insulation that is blown or fabricated from wood fibers, cork boards or expanded cork can be an environmentally friendly option. These types of insulation are typically manufactured in Europe, so they may have a larger carbon footprint when shipped to the United States.
Another alternative to natural materials is fiberglass. This is made from recycled glass, plastic and other materials. It can be a great choice for many types of buildings, but it has several downsides. It can cause irritation to the respiratory tract and it is not a good choice for people with asthma. It is also not an effective insulator and can become contaminated with mold or mildew.
The most environmentally friendly insulation material is found to be made from miscanthus. Compared with stone wool, this bio-based insulation material has the lowest environmental burden per functional unit (FU). Similarly to cellulose and wood fiber, a high proportion of energy is required for cultivation, but this is compensated by a low energy consumption in use phase.
Air Pollution
Insulation helps to reduce the amount of energy that is used in a building, making it more energy efficient. But many people are concerned that the insulation products themselves can have a negative impact on the environment. Fortunately, there are some types of insulation that are more environmentally friendly than others.
Cellulose and polyester are both made from recycled materials, and as such have a much lower environmental impact than some other insulation products. These include fiberglass and extruded polystyrene (XPS). These products use fossil fuels during their manufacturing process, and also release a lot of greenhouse gases. They also require toxic chemicals such as isocyanates and polyols, and often need flame retardants which can be harmful to the human body.
Fossil and mineral insulation materials dominate the market, but bio-based alternatives are available. Numerous life cycle assessments have shown that bio-based insulation materials offer the same or even greater benefits than nonrenewable insulations. However, a comparative LCA with a life cycle costing (LCC) performed under equal conditions is necessary to identify the most environmentally friendly and cost-efficient insulation material. The comparative LCA and LCC investigated four bio-based insulation materials—wood fiber, hemp fiber, flax, and miscanthus—and two nonrenewable ones—expanded polystyrene (EPS) and stone wool. Eighteen impact categories were assessed and the results showed that wood fiber and miscanthus were more environmentally friendly than EPS and stone wool in 11 of the impact categories.
Water Pollution
Using insulation that is easy to recycle at the end of its life can reduce the demand on the world’s natural resources. It can also reduce the amount of pollution created during its production process. Some insulation products are manufactured from materials that are not sustainable or require chemicals that have a bad impact on the environment.
The insulation industry is among the main industrial sectors contributing to environmental impacts. Currently, fossil and mineral insulations dominate the market despite numerous life cycle assessments (LCA) that show that renewable insulation materials have the potential to decrease the overall energy consumption of buildings.
Fossil and mineral based insulation materials are energy inefficient and produce high greenhouse gas emissions. However, it is possible to find insulation options that offer a better balance between energy efficiency and environmental impact by choosing the right type of material.
In order to identify the best option in terms of environmental performance and cost-efficiency, a cradle-to-grave LCA and LCC for four bio-based and two nonrenewable insulations were conducted. The insulations evaluated were made from wood fiber, cellulose, flax, and hemp, and compared to the nonrenewable insulations EPS and stone wool. All analyses were performed using the standardized model EF 3.0, which is an extension of IEA’s LCTA. The assumptions and methodologies applied were chosen to increase the comparability of the results. This included a uniform system boundary and a definition of the raw material systems in an equal way.